Shark Spotters is often asked how effective the electric shark repellent Shark Shield TM is. In 2010 and 2011 we collaborated on the first scientific study to test their effectiveness on repelling white sharks.

Press release from South Australia Research and Development Institute (SARDI)

A two-year study of shark behaviours has given scientists a greater insight into how sharks respond to electric deterrents worn by divers and surfers.

The study, prepared by SARDI/Flinders University Shark Ecologist Dr Charlie Huveneers for Safework SA, tested the behaviours of white sharks when exposed to the Shark Shield Freedom7TM.

“The aim of the project was to improve our understanding of how these devices affect the behaviour of white sharks,” Dr Huveneers said.

The effects of the electric deterrent were tested in two different situations and locations: on a static tuna bait at the Neptune Islands off South Australia and on a dynamic seal decoy at Seal Island off South Africa.

The trials showed no evidence that the deterrent attracted white sharks, said Dr Huveneers. “Furthermore, results demonstrated that the deterrent had an effect on the behaviour or white sharks, but did not deter or repel them in all situations.”

Results showed that the distance at which white sharks turned away from a tuna bait tended to increase when the deterrent was activated. Also, no targeted predatory approaches by sharks were observed, and the total number of interactions with the seal decoy was significantly less when the deterrent was activated.

Dr Huveneers said “The deterrent did not reduce the proportion of tuna baits consumed, while white sharks were observed within 0.5 m of the deterrent when it was activated”.

Future research should focus on mapping the field emitted by the electric deterrent, testing the effect of deterrents less than two metres from the bait and on other potentially dangerous sharks, such as tiger sharks and bull sharks, said Dr Huveneers.

“We have improved our understanding of how white sharks react to electric deterrents, but it is still unknown whether other species would react similarly or how sharks might be affected by electric deterrents in other situations,” he said.